| 摘要 |
PURPOSE:To prevent the malfunction of a single gate type field effect transistor caused by hot carrier effect, without damaging electric writing function of a stacked gate type field effect transistor by decreasing the impurity concentration of the peripheral part of source and drain of the single gate type field effect transistor. CONSTITUTION:In a semiconductor device in which a stacked gate type field effect transistor F and a single gate type field effect transistor S are formed, the single gate type field effect transistor S only is provided with the source.drain of double diffusion structure having a low impurity concentration region 12. For example, a silicon dioxide insulating film 2 and a first polycrystalline silicon layer 3 are formed on a P-type silicon substrate 1; a gate electrode 10 of the transistor S is formed; the low impurity concentration region 12 is formed by ion-implanting N-type impurity; a second silicon dioxide insulating film 4 is formed; a second polycrystalline silicon layer 5 is formed; a gate electrode 9 is formed; the source.drain 11 is formed by ion-implanting N-type impurity. |
